Technological innovations in wireless systems and devices have lead to widespread development of wireless network applications for wireless PAN (personal area network), wireless LAN (local area network), wireless WAN (wide area network), cellular networks, and other types of wireless communication systems. To enable wireless communication between devices in a wireless network, the devices must be equipped with receivers, transmitters, or transceivers, as well as antennas that can efficiently radiate/receive signals transmitted to/from other devices in the network.
Conventional MMW (millimeter-wave) radio communication systems are typically constructed using discrete components that are individually encapsulated and/or mounted with low integration levels on printed circuit boards, packages or substrates. For example, MMW radio communication systems are typically built using expensive and bulky wave guides and/or package-level or board-level microstrip structures that provide electrical connections between semiconductor chips (RF integrated circuits) and between semiconductor chips and transmitter or receiver antennas.
There is an increasing market demand, however, for more compact radio communication systems with integrated transmitter/receiver/transceiver and antenna systems, which provide high-performance, high data transmission rate, high-volume, low-power consumption, low cost, and low weight solutions. Indeed, current communication systems require high performance antenna systems that provide wide bandwidth and high-efficiency operating characteristics. As the operating frequency increases, the manufacture and assembly of conventional waveguide front-ends become more difficult. In this regard, innovations in semiconductor fabrication and packaging technologies, coupled with requirements for higher operating frequencies, have made it practically feasible for integrating antennas with RF integrated circuits to provide highly integrated radio communication systems.
With increased integration, however, the ability to achieve high performance systems becomes more problematic, especially at millimeter wave frequencies wherein the structure and EM characteristics of the integrated antenna system will determine the achievable performance of the system. With high-integration designs, design tradeoffs are typically made with respect to antenna performance (e.g., tradeoffs between antenna bandwidth and efficiency).